// filename:c2011-6-7-2-3-ex.c
// original examples and/or notes:
// 		(c) ISO/IEC JTC1 SC22 WG14 N1570, April 12, 2011
// http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1570.pdf
// 			C2011 6.7.2.3 Tags
// compile and output mechanism:
// 		(c) Ogawa Kiyoshi, kaizen@gifu-u.ac.jp, December.xx, 2013
// compile errors and/or wornings:
// 1	(c) Apple LLVM version 4.2 (clang-425.0.27) (based on LLVM 3.2svn)
// 			Target: x86_64-apple-darwin11.4.2 //Thread model: posix
// 		(c) LLVM 2003-2009 University of Illinois at Urbana-Champaign.
// 2    gcc-4.9 (GCC) 4.9.0 20131229 (experimental)
//      Copyright (C) 2013 Free Software Foundation, Inc.
#include <stdio.h>
int main(void)
{
// Example 1
struct tnode {
	int count;
	struct tnode *left, *right;
	};
struct tnode s, *sp;
// Example 2	
struct s1 { struct s2 *s2p; /* ... */ }; // D1
struct s2 { struct s1 *s1p; /* ... */ }; // D2
struct s2;
return printf("6.7.2.3 Tags %d %d\n",s.count,sp);	
}
// output LLVM3.2 
// 6.7.2.3 Tags 0 0
// output GCC4.9
//6.7.2.3 Tags 0 1777213534